Mason admitted yesterday that he had been fired from the daily deals site he founded a day after it reported another disappointing quarter, sending the stock plunging 25 percent.

“After four and a half intense and wonderful years as CEO of Groupon, I’ve decided that I’d like to spend more time with my family. Just kidding — I was fired today,” Mason wrote in a farewell note to staff that he also tweeted.

His message poked fun at everything from his troubled run atop the company to his need for “fat camp” after gaining the “Groupon 40.”

Mason can still take comfort in his millions. He reaped about $30 million from selling shares and holds about $220 million worth of stock. Of course, his stake used to be worth a lot more — almost $1 billion — when the much-hyped company went public at $20 a share in November 2011.

While Mason owns 20 percent of the voting shares, co-founders Eric Lefkofsky and Bradley Keywell own more. Lefkofsky will share CEO duties with Groupon board member and former AOL heavyweight Ted Leonsis while the company searches for a new CEO.

Investors grew impatient with Mason as Groupon stumbled badly, missing expectations the past two quarters. It was a stunning reversal for a company that famously rejected a $6 billion takeover offer from Google.

Mason said he hoped his departure would revive Groupon’s sagging stock price for the benefit of employees and investors. Shares rose 7 percent on the news of his exit.